Such an installation is known from the DE C1 34 27 716. It concerns an installation for hardening individual parts comprising a rotary hearth furnace and a hardening press. The rotary hearth furnace has a sluice-like charging or discharging zone which is formed by means of vertically movable doors arranged on either side of the charging and discharging opening. Once the furnace door has been opened, the parts can be removed individually from this charging or discharging zone by means of a charging and discharging robot and conveyed into the hardening press.
There is need for the installation is to be used more universally, i.e. to permit not only the heat-treating of individual parts but also the heat-treating of entire charges located on charge carriers, e.g. grates. Whole charges of parts are generally quenched in a quenching bath.
The cycle time, i.e. the time between placing a part in the rotary hearth furnace and removing it from the rotary hearth furnace is relatively long with the known installation as only one opening is used for both charging and discharging. Therefore, it is also necessary to minimise the cycle time.
Therefore, the object of the present invention was to create an installation of the type described above which is universal and which has a short cycle time.